#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
int main() 
{
    int a = 0;
    int b = 0;
    int c = 0;
    while (scanf("%d %d %d", &a, &b, &c) == 3) 
    {
            if (a + b > c && a + c > b && b + c > a)
            {
                if (a == b && b == c && a == c)
                    printf("Equilateral triangle!\n");
                else if (a == b || b == c || a == c)
                    printf("Isosceles triangle!\n");
                else  
                    printf("Ordinary triangle!\n");
            }
            else 
            {
                printf("Not a triangle!\n");
            }
    }
    return 0;
}